Abstract

Human performance results from an interaction between circadian rhythmicity and homeostatic sleep pressure. Whether and how this interaction is represented at the regional brain level is not established. We quantified changes in brain responses to a sustained-attention task during 13 functional magnetic resonance imaging (fMRI) sessions scheduled across the circadian cycle during 42h of wakefulness and following recovery sleep, in 33 healthy participants. Cortical responses showed significant circadian rhythmicity, the phase of which varied across brain regions. Cortical responses also significantly decreased with accrued sleep debt. Subcortical areas exhibited primarily a circadian modulation, which closely followed the melatonin profile. These findings expand our understanding of the mechanisms involved in maintaining cognition during the day and its deterioration during sleep deprivation and circadian misalignment.

This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in Science on 12 August 2016 Vol 353, DOI: 10.1126/science.aad2993